Preliminary investigation on the use of low current pulsed power Z-pinch plasma devices for the study of early stage plasma instabilities

Abstract

This article addresses key features for the implementation of low current pulsed power plasma devices for the study of matter dynamics from the solid to the plasma phase. The renewed interest in such low current plasma devices lies in the need to investigate methods for the mitigation of prompt seeding mechanisms for the generation of plasma instabilities. The low current when driven into thick wires (skin effect mode) allows for the simultaneous existence of all phases of matter from solid to plasma. Such studies are important for the concept of inertial confinement fusion where the mitigation of the instability seeding mechanisms arising from the very early moments within the target's heating is of crucial importance. Similarly, in the magnetized liner inertial fusion concept it is an open question as to how much surface nonuniformity correlates with the magneto-Rayleigh-Taylor instability, which develops during the implosion. This study presents experimental and simulation results, which demonstrate that the use of low current pulsed power devices in conjunction with appropriate diagnostics can be important for studying seeding mechanisms for the imminent generation of plasma instabilities in future research.

The importance of the laser pulse-ablator interaction dynamics prior to the ablation plasma phase in inertial confinement fusion studies

“…Recently, we demonstrated a new type of instability which originates in the TEP phase of heated solid targets in pulsed nanosecond rise time, kA current heated wires named the electro-thermo-mechanical (ETM) instability [28,39]. The ETM instability exists in a material because the electrical conductivity as well as the elastoplastic properties of the material depend on temperature.…”

“…The FEM is used to simulate the early time dynamics of the heated ablator until the end of the TEP and melting phases of the interaction. To simulate the physical problem a pure thermo-structural (TS) model is developed [27,28]. The three-dimensional-coupled TS-FEM simulation conveys a simultaneous solution of the heat conduction and the mechanical motion equations [27,28].…”

“…To simulate the physical problem a pure thermo-structural (TS) model is developed [27,28]. The three-dimensional-coupled TS-FEM simulation conveys a simultaneous solution of the heat conduction and the mechanical motion equations [27,28]. The mechanical equation determines the displacements of the target and the heat conduction equation predicts the temperature distributions, imposed by the heating source of the target.…”

“…In our study, the coefficients b and d , being the only free parameters in the model, are evaluated by comparing the simulated perturbation amplitudes with the experiments. Further insights into the involved multiphysics as well as details for the FEM modelling can be found in our previous published work [27,28,39–44].…”

High-intensity laser-driven secondary radiation sources using the ZEUS 45 TW laser system at the Institute of Plasma Physics and Lasers of the Hellenic Mediterranean University Research Centre

“…Besides their use for the generation of XUV radiation for dense plasma diagnosis, they are excellent devices for basic plasma physics studies such as for instance plasma instabilities grow. The technical parameters and specifications of these devices can be found in [91][92][93][94][95]. Upon request the devices can be offered to users either as hard X/XUV radiography diagnostics synchronised to the ZEUS laser or as individual plasma sources for experiments.…”